Heat-treated iron(III) tetramethoxyphenyl porphyrin chloride supported on high-area carbon as an electrocatalyst for oxygen reduction - Part II. Kinetics of oxygen reduction
Heat-treated iron(III) tetramethoxyphenyl porphyrin chloride supported on high-area carbon as an electrocatalyst for oxygen reduction - Part II. Kinetics of oxygen reduction
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DOI：
10.1016/s0022-0728(98)00390-8
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发表时间：
1999-02-08
影响因子：
4.5
通讯作者：
Savinell, RF
中科院分区：
文献类型：
--
作者：
Gojkovic, SL;Gupta, S;Savinell, RF
在吸附在黑珍珠碳上的FeTMPP-Cl处研究氧还原，并在200至1000 ℃的温度下热处理。在酸性和碱性介质中建立了反应动力学参数和反应速率对热处理温度的依赖性。发现O-2还原速率随着电催化剂的热处理温度的增加而增加，在小于或等于1000 ℃的T小于或等于700 ℃时达到平台。在碱性溶液中的反应速率较高的所有电催化剂检查，但其对热处理温度的依赖性是相同的，在酸性介质。与其它大环催化剂一样，FeTMPP-Cl/BP具有较好的耐甲醇性能。考察了硫酸根、高氯酸根和磷酸根阴离子对反应速率的影响，并比较了FeTMPP-Cl/BP和Pt/BP电催化剂的活性。如果在碱性溶液中比较，在小于或等于1000 ℃的T小于或等于700 ℃下热处理的FeTMPP-Cl/BP显示出与Pt/BP相似的活性，但是在酸性溶液中，在Pt电催化剂上的反应速率更高。讨论了文献中关于金属Fe颗粒在O-2还原催化中的作用的争议。本结果与以前的循环伏安法和TEM研究相同的电催化剂的比较，进一步证明，一些其他产品的热处理是负责催化剂的高活性。(C)1999年Elsevier Science S.A. All rights reserved.
Oxygen reduction was investigated at FeTMPP-Cl adsorbed on the Black Pearls carbon and heat-treated at temperatures from 200 to 1000 degrees C. Kinetic parameters of the reaction and the dependence of the reaction rate on the heat-treatment temperature were established in acid and alkaline media. It was found that the O-2 reduction rate increases with increase in the heat-treatment temperature of the electrocatalyst, reaching a plateau at 700 less than or equal to T less than or equal to 1000 degrees C. The reaction rate was higher in alkaline solution on all electrocatalysts examined, but its dependence on the heat-treatment temperature was the same as in acid media. Like similar other macrocycle catalysts, FeTMPP-Cl/BP was found to be methanol-tolerant. The effect of sulfate, perchlorate, and phosphate anions was also investigated and no influence on the reaction rate was found. Activities of FeTMPP-Cl/BP and Pt/BP electrocatalysts were compared. FeTMPP-Cl/BP heat-treated at 700 less than or equal to T less than or equal to 1000 degrees C showed similar activity to Pt/BP if they are compared in alkaline solution, but in acid solution, the reaction rate on the Pt electrocatalyst was higher. The controversy in the literature on the role of metallic Fe particles in O-2 reduction catalysis is discussed. Comparison of present results with previous cyclic voltammetry and TEM investigations of the same electrocatalyst gave further evidence that some other products of the heat-treatment are responsible for the high activity of the catalyst. (C) 1999 Elsevier Science S.A. All rights reserved.